Step children

If a step father has been a father figure for most of children's life, there bio father was no contact, did pay maintenance but he is now deceased so she will have to provide entirely on her own. Is step father required to help?
5 years marriage, 7/8 living together.
Step father doesn't work.
Would it be a mistake for wife to move into rented, would this make her and the children adequately housed and so affect the financial settlement ? Despite the cost of rent and children being crippling.
marital home in husbands name, mortgaged before marriage equity approx 260,000. He is also due inheritance approx 100,000

It will depend on whether a court considers them "children of the family" although if the step father doesn't work then it might be more expense than it's worth to find out?

If he hasn’t adopted them then he has no ongoing responsibility for them.

Pot may be split in ex wife favour if needs be to house them.

Did they get anything from their late fathers estate or a pension?

No they got nothing. So if she leaves the marital home and finds rental will that go against her because her housing needs are met.

No, that's a bit of a myth. In the real world a court wouldn't award 100% of the FMH to the person who stayed because the other can rent. The decision would be patently unfair. What could happen though is that the property could take longer to sell if the occupant was not motivated to get a move on.

Thank you. Bit of a tough choice renting to keep sanity but being worse off financially for it!